You know the one I’m talking about. The little bar at the bottom of the browser that goes from left to right as a new web page loads. The one that whizzes by on most sites, but takes forever on the SDMB:(
What is this bar a measure of? Is it counting bytes of content received from the server? Does it know how many bytes to expect so it can calculate a percentage? In short, what is this bar telling me in quantifiable terms?